A target of 159 was set for the Proteas at the Dubai International Cricket Stadium in the United Arab Emirates as Amelia Kerr top-scored for the White Ferns with 43 runs, while Brooke Halliday scored 38.
Nonkululeko Mlaba picked up two wickets for the Proteas as New Zealand posted 158-5 in their 20 overs.
Amelia Kerr and Rosemary Mair both claimed three wickets as South Africa were restricted to 126-9 in the chase.
South Africa have yet to win the tournament and were also defeated as finalists at the last edition. #icccricket #crickett20